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arXiv · hep-th/0507143

Classical resolution of singularities in dilaton cosmologies

E. A. Bergshoeff·A. Collinucci·D. Roest·J. G. Russo·P. K. Townsend
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Abstract

For models of dilaton-gravity with a possible exponential potential, such as the tensor-scalar sector of IIA supergravity, we show how cosmological solutions correspond to trajectories in a 2D Milne space (parametrized by the dilaton and the scale factor). Cosmological singularities correspond to points at which a trajectory meets the Milne horizon, but the trajectories can be smoothly continued through the horizon to an instanton solution of the Euclidean theory. We find some exact cosmology/instanton solutions that lift to black holes in one higher dimension. For one such solution, the singularities of a big crunch to big bang transition mediated by an instanton phase lift to the black hole and cosmological horizons of de Sitter Schwarzschild spacetimes.

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E. A. Bergshoeff, A. Collinucci, D. Roest, J. G. Russo, P. K. Townsend. 2005-10-10. Classical resolution of singularities in dilaton cosmologies. https://doi.org/10.1088/0264-9381%2F22%2F22%2F008

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